原型扩展的方法解决IE和Firefox的Js兼容问题

if(!document.all){
//textContent->text
   Element.prototype.__defineGetter__('text',function(){return this.textContent===undefined?this.text:this.nodeType?this.textContent:undefined;});
   Element.prototype.__defineSetter__('text',function(txt){this.textContent=txt;});

//让firefox文本节点支持text属性
   Text.prototype.__defineGetter__('text',function(){return this.textContent===undefined?this.text:this.nodeType?this.textContent:undefined;});
   Text.prototype.__defineSetter__('text',function(txt){ this.textContent = txt;});

//serializeToString->xml 只读
   Element.prototype.__defineGetter__('xml',function(){return this.nodeType?(new XMLSerializer()).serializeToString(this):null;});

//addEventListener->attachEvent
   HTMLElement.prototype.attachEvent = function(ev, fn){
       ev = ev.toLowerCase();
       this.addEventListener(ev.indexOf('on')===0?ev.substr(2):ev, fn, false);
   };
//removeEventListener->detachEvent
   HTMLElement.prototype.detachEvent = function(ev, fn){
       ev = ev.toLowerCase();
       this.removeEventListener(ev.indexOf('on')===0?ev.substr(2):ev,fn);
   };

   if(self!=top){ //为移动xWin定义事件,document为xWin下的document
      var doXwinMv=false; //用于修正移动xWin后其中的文本会被选中的问题
      document.addEventListener('mousedown', function(ev){ mouseOffset={x:ev.pageX, y:ev.pageY} });
      document.addEventListener('mousemove', function(ev){ top.mouseMove(ev); });
      document.addEventListener('mouseup', function(ev){ top.mouseUp(ev);if(window.getSelection() && doXwinMv) window.getSelection().collapseToStart(); doXwinMv=false;});
   }

   //修正firefox下xWin背景色为黑色的问题
   //if(!window.getComputedStyle(document.documentElement,null)['backgroundColor']) document.documentElement.style.backgroundColor = '#fff';
   //document.documentElement.style.backgroundColor = '#fff';

//让firefox支持innerText属性
   HTMLElement.prototype.__defineGetter__("innerText",function(){
       var textRange = this.ownerDocument.createRange();
       textRange.selectNodeContents(this);
       return textRange.toString().replace(/ /g,'');
   });
   HTMLElement.prototype.__defineSetter__("innerText",function(str){
       this.textContent = str;
   });

//修正firefox下firstChild lastChild获取到的是空白行文本节点的问题
   Element.prototype.__defineGetter__('firstChild',function(){
   var firstEleNode = firstNode = null;
   firstNode = this.childNodes[0];
   while (firstNode && firstNode.nodeType===3 && firstNode.nodeValue==' '){//若是空白行文本节点则继续往后查找
       firstNode = firstNode.nextSibling;
   }
   firstEleNode = firstNode;
   return firstEleNode;
   });

   Element.prototype.__defineGetter__('lastChild',function(){
       var mIdx = this.childNodes.length-1;
       var lastNode = lastEleNode =null;
       lastNode = this.childNodes[mIdx];
       while(lastNode && lastNode.nodeType===3 && lastNode.nodeValue===' '){//若是空白行文本节点继续往前查找
           lastNode = lastNode.previousSibling;
       }
       lastEleNode = lastNode;
       return lastEleNode;
   });

//后台返回xml文档后，遍历节点会遍历到空白行文本节点所以需要这个方法先删除空白行文本节点属性节点也是子节点？？
   Element.prototype.__defineGetter__('delEmptyLineNode',function(){ //注意：document文档节点没继承该属性 document.documentElemnt根节点继承了该属性
       function delEmpty(node){
           var chNodes=node.childNodes, re=/^s+$| | /m;
           for(var i=0, len=chNodes.length; i<len; i++){
               if (chNodes[i] && chNodes[i].nodeType===1){
                   if(chNodes[i].childNodes.length===1){ //叶子节点

                   }else{ //非叶子元素节点递归
                       delEmpty(chNodes[i]);
                   }
               }else if(chNodes[i] && chNodes[i].nodeType===3 && re.test(chNodes[i].nodeValue)){//空白文本节点
                   node.removeChild(chNodes[i]);
                   --i;
               }
           }
       }
       delEmpty(this);
       return this;
   });


//xmlNode.selectNodes()方法只支持ie, 在当前xml节点下查找节点, Firefox下为Element原型定义同名属性
   Element.prototype.selectNodes = function(xpathStr){
       if(xpathStr.charAt(0)=='/') xpathStr="."+xpathStr;
       var snapshot = this.ownerDocument.evaluate(xpathStr, this, null, 7, null);
       var nodes = [];
       for(var i=0; i<snapshot.snapshotLength; i++){
           nodes.push(snapshot.snapshotItem(i));
       }
       return nodes;
   };

   Element.prototype.selectSingleNode = function(xpathStr){
       return this.selectNodes(xpathStr)[0];
   };
//ie怪异模式下可以node.children(2)这样获取第3个子节点，firefox或ie9等现代浏览器都不行，firefox修改同名属性children为children()方法来兼容
//注:children重定义后,children[0]这样的写法将不可用
   Object.defineProperty(Element.prototype, 'children',{value:function(i){return this.delEmptyLineNode.childNodes[i];}, writable:true, enumerable:true, configurable:true});

//(new DOMParser())).parseFromString(xmlStr, 'text/xml') --> loadXML
   XMLDocument.prototype.loadXML = function(xmlStr){
           return (new DOMParser()).parseFromString(xmlStr,'text/xml');
   };

//让firefox支持insertAdjacentElement
   HTMLElement.prototype.insertAdjacentElement = function(sWhere, insEle){
       if(!insEle.nodeType) return;
       this.insertAdjacentHTML(sWhere,insEle.xml);
   };
//让firefox支持ie事件对象的相关属性
//-- returnValue --
   Event.prototype.__defineSetter__("returnValue", function(b){
       if(!b) this.preventDefault();
       return b
   });
//-- cancelBubble --
   Event.prototype.__defineSetter__("cancelBubble", function(b){
       if(b) this.stopPropagation();
       return b;
   });
//--- srcElement ---
   Event.prototype.__defineGetter__("srcElement", function(){
       var node = this.target;
       while(node.nodeType !== 1) node = node.parentNode;
       return node;
   });
//--- fromElement ---
   Event.prototype.__defineGetter__("fromElement", function(){
       var node;
       if(this.type == 'mouseover'){ node = this.relatedTarget;}
       if(this.type == 'mouseout'){ node = this.target; }
       if(!node) return null;
       while(node.nodeType!=1){ node = node.parentNode; }
       return node;
   });
//--- toElement ---
   Event.prototype.__defineGetter__("toElement", function(){
       var node;
       if(this.type == 'mouseover'){ node = this.target; }
       if(this.type == 'mouseout' ){ node = this.relatedTarget; }
       if(!node) return null;
       while(node.nodeType!=1){ node = node.parentNode; }
       return node;
   });

//让firefox下table支持moveRow方法
   HTMLElement.prototype.moveRow = function(srcIdx, targetIdx){
       var re = /^(table|tbody|tfoot|thead)/i;
       if(!re.test(this.nodeName) || srcIdx === targetIdx) return;
       var pNode, srcR,targetR;
       pNode = this;
       if(this.nodeName.toLowerCase() === 'table') pNode = this.getElementsByTagName('tbody')[0]; //firefox 自动插入tbody
       //targetIdx<srcIdx 行往前面移直接pNode.insertBefore()即可
       srcR = pNode.rows[srcIdx];
       targetR = pNode.rows[targetIdx];
       if(!srcR || !targetR) return; //索引范围以外则返回
       targetRnext = pNode.rows[targetIdx+1] || null;
       if(targetIdx < srcIdx) pNode.insertBefore(srcR, targetR);
       if(targetIdx > srcIdx) pNode.insertBefore(srcR, targetRnext);
   };

//让firefox下的styleSheet对象支持rules属性
   CSSStyleSheet.prototype.__defineGetter__('rules', function(){return this.cssRules});

//让firefox支持currentStyle 注意color样式值会转换为 rgb(233,22,22)的形式
   HTMLElement.prototype.__defineGetter__('currentStyle',function(){return window.getComputedStyle(this,null);});

//firefox createElementX
   HTMLDocument.prototype.createElementX = function (tag){
       var re=/^<.+>$/;
       if(re.test(tag)){ //<p ...></p> < ...>
           try{
               var tmpDiv = this.createElement('div'); //临时div
               tmpDiv.innerHTML = tag;
               return tmpDiv.firstChild;
           }catch(err){alert(err.message);}
       }else{ // p, div...
           try{
               return document.createElement(tag);
           }catch(e){alert(e.message)}
       }
   }

}//For Firefox End